选择题:若a、b、c为不等于0的数,且a分之1+b分之1+c分之1=a+b+c分之1,则a、b、c三数（ ）A.必定有两个互为相反数. B.必有两个相等 . C.必定同号. D.以上结论都不对.

相关推荐

• 选择题:若a、b、c为不等于0的数,且a分之1+b分之1+c分之1=a+b+c分之1,则a、b、c三数（ ）A.必定有两个互为相反数. B.必有两个相等 . C.必定同号. D.以上结论都不对.
• 有理数加法（1）若a小于0,b大于0,且a+b小于0,比较a,b,-a,-b的大小,用“《”连接为（ ）（2）若a小于0,b大于0,且|a|小于|b|.则a+b（ ）0（3）若|x|+（-一又三分之二）=1.那么x的值为（）{可以填俩个}（4）下列说法正确的是（）A.两个数之和大于每一个加数B.两个数之和为正,则两个加数均正C.两个数之和为负,则两个加数均负D.两个数之和为零,这两个数必互为相反数（5）下列说法正确的是（ ）A.若|a|=m,|b|=n,则|a+b|=m+nB.对于任意有理数,如果a不等于0,b不等于0,则a+b不等于0C.对于任意有理数,如果|a|=|b|,则a+b=0D.对于任意有理数,如果a+b=0,则|a|=|b|
• 这道题选c,具体是怎么做的呢.函数y=xsinx+cosx在下面哪个区间内是增函数A（π/2,3π/2)B（π,2π）C（1.5π,2.5π）D（2π,3π）
• 1.My little brother looks forward to____ DisneylandA.visit B.visiting C.visiting to D.visit to2.Do you know ____?A.where was Confucius bornB.when was Confucius bornC.where Confucius was bornD.Which Confucius was born3.Do you have enough men to carry these chairs?No,i think we need___ men A.another B.two others C.more two D.two more4.Not only Jim but also his sister __ a few cities in the south since they came to China.5.We found___ necessary to protec